Recent studies on polymerization using transition metal complexes as catalyst are reviewed. Ti, W, and Ru complexes catalyze ring opening metathesis polymerization of cyclic olefins such as norbornene and cyclooctene to give the corresponding polymers. Living polymerization is achieved in many cases. Structures and reactivities of cyclopentadienyl complexes of Ti, Zr, and Hf are investigated in order to elucidate reaction mechanism of olefin polymerization catalyzed by Kaminsky system. Transition metal complex catalyzed synthetic organic reactions such as carbonylation of organic halides, arylation of olefins as well as cross-coupling of Grignard reagents with organic halides have been applied to preparation of various polymers. Coupling reaction of aryl halides promoted by Ni complex is developed to preparation of π-conjugated polymers which show interesting electrical and optical properties.
Weight loss and characterization of straight chain saturated fatty acids (even-numbered fatty acids : 8 kinds, odd-numbered fatty acids : 7 kinds) were studied by dynamic programmed thermogravimetry (TG), derivative thermogravimetry (DTG) and differential scanning calorimetry (DSC). 1) Initial weight losses and weight loss curves of straight chain fatty acids under air and under nitrogen shifted only to the higher-temperature side with increase in carbon number. Weight loss patterns were simple and essentially the same to each other. The DSC curve of each fatty acid under air differed markedly from that under nitrogen. The curves of fatty acids under nitrogen shifted to the endothermic side. Under air, the DSC curves of fatty acids ranging from heptanoic to tridecanoic acids, also shifted to the endothermic side. However, the curves of fatty acids having carbon numbers exceeding that of tetradecanoic acid shifted to the exothermic side. 2) GLC analysis of volatile and residual substances at the temperature corresponding to 25 % weight loss on TG indicated to the weight loss of fatty acid until to possibly be due primarily to evaporation of the fatty acid. However, the residual rate after the peak temperature of DTG increased with carbon number, this being particularly evident in the case of exposure to the air flow. Weight loss in the air flow is thus shown to be accompanied by decomposition. 3) The peak temperature of DTG curve was closely correlated to fatty acid boiling point. However, the regression line in the air flow was situated on the lower-temperature side than that in the case of the nitrogen flow, due to accompanying decomposition.
Reacted mixtures obtained by the esterification of three purified fatty acids (oleic acid, icosapentaenoic acid, and docosahexaenoic acid) with glycerol were separated and purified into triacylglycerol, diacylglycerol, monoacylglycerol, and free fatty acid fractions by centrifugal partition chromatography (CPC). Two solvents were used in combination for the separation. One phase was hydrocarbon and the other, a water-miscible solvent. n-Hexane and 85 % ethyl alcohol were used in this study. According to polarity, MG, FFA, and DG were extracted into 85 % ethyl alcohol fractions, and TG was extracted into n-hexane. When mixtures more than 10 g were charged, TG and the other components could be extracted easily with total recovery higher than 90 %.
For the quantitative estimation of yellowing due to the oxidation of oily soils, and their detergency, the autoxidation and yellowing of linoleic acid in the bulk phase were investigated by UV spectroscopy. The oxidized products were quantitatively separated by the TLC-FID method. UV spectroscopy showed oxidation to occur more rapidly when more oxygen was present, and to be inhibited by the radical scavenger, galvinoxyl. A quantitative determination of oxidized products was possible by the TLC-FID method. A good linear relationship was observed between amounts of oxidized products and integral intensities of the UV spectra at 235 nm and 270 nm.
Volatile oils were obtained by the steam distillation of fruits [A], roasted fruits [B] and Yokuinin (COICIS SEMEN) [C]. The oil yields were 0.05 % for [A], 0.05 % for [B] and 0.04 % for [C]. The components of the volatile oils were determined by IR, GC, and GC-MS. Sixty-eight, sixty-one and sixty-nine components from [A], [B] and [C] oils, respectively, were definitely or tentatively identified. [A], [B] and [C] oils possessed a green, savory and fatty acid note, respectively. The major common components of [A], [B], and [C] oils were carbonyl compounds and carboxylic acids such as hexanal, vanillin, hexanoic acid, octanoic acid and palmitic acid. Characteristic volatile flavor components in [A] oil were hexanal, 1-pentanol, 2-decanone, 2-decanal, and in [B] were benzofuran, 2-ethyl-3-hydroxyhexyl butyrate, dihydroactinidiolide, 1-tetradecanol, dihydrobenzofuran, vanillin, and in [C], hexanal, hexanoic acid, 2-ethyl-3-hydroxyhexyl butyrate, γ-nonalactone, nonanoic acid, octanoic acid, ethyl palmitate, methyl linoleate, vanillin and ethyl linoleate.
Acidolysis and interesterification catalyzed by immobilized Lipase TOYO (Chromobacterium viscosum) in hexane have been studied to find a means of incorporating icosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) into triolein using free fatty acids and their ethyl esters as substrates. The fatty acids (EPA and DHA) were incorporated at about 40 %, while their esters only at about 10 %. The acidolysis of fish oil (sardine oil and yellowfin tuna eye socket oil) with EPA and DHA gave n-3-polyunsaturated fatty acid (PUFA) rich triglyceride (EPA+DHA incorporation higher than 60 %). The immobilized enzyme may thus be considered useful for producing n-3-PUFA rich oil.
After isolating components 1' and 2 from heat-treated solution of bovine serum albumin (BSA), their interactions with bilirubin were studied under the same conditions as in the previous study. Spectrophotometric and fluorescence measurements were made at pH 7.5 and 25°C. 1) Comparisons were made of n and K for components 1' and 2 with those for components N (native BSA). That the highest-affinity binding site for bilirubin on the denatured forms appeared to be damaged slightly. 2) Comparisons were made of values of εb(485 nm) for components 1' and 2 with that for component N. The environment of the site for the interaction for the component N differed from that of denatured forms. Those of the site were the same in components 1' and 2. 3) The fluorescence spectrum of the system of component N and bilirubin differed from that of th system of denatured components and bilirubin. The same conclusion as in (2) would thus appear to apply.
The isomerization of terpinolene oxide (1) in the presence of montmorillonite K-10 catalyst was studied. High selectivity of Karahanaenone [(2), 2, 2, 5-trimethy1-4-cyclohepten-1-one, isolated yield 82 %] was attained by the simple solid-liquid phase heterogeneous reaction.
A dozen brands of commercially available cooking oils were investigated by analyzing their fatty acids, sterols, tocopherols, emulsifiers, heavy metals and by examining oxidative stabilities at 60°C. 1) The oils tested were composed mainly of C18:1, C18:2 along with small amounts of saturated fatty acids, but C15, C17 and trans fatty acids were not detected. Hydrogenated oils and animal fats were thus not blended in the oil. 2) Lecithin was detected 0.10-2.06 % in all samples, but monoacylglycerols could be found in only 3 samples. No other emulsifiers were detected in all the samples. No correlation could be found between lecithin and monoacylglycerols contents. 3) Oxidative stability of the samples depended on the lecithin content, but was not affected by that of iron or tocopherols.